U.S. patent application number 12/782204 was filed with the patent office on 2010-11-25 for functional film, method for manufacturing functional film, and apparatus for manufacturing functional film.
This patent application is currently assigned to FUJIFILM CORPORATION. Invention is credited to Jun Fujinawa, Eijirou Iwase.
Application Number | 20100297473 12/782204 |
Document ID | / |
Family ID | 43124759 |
Filed Date | 2010-11-25 |
United States Patent
Application |
20100297473 |
Kind Code |
A1 |
Iwase; Eijirou ; et
al. |
November 25, 2010 |
FUNCTIONAL FILM, METHOD FOR MANUFACTURING FUNCTIONAL FILM, AND
APPARATUS FOR MANUFACTURING FUNCTIONAL FILM
Abstract
A method for manufacturing a functional film, includes the steps
of: continuously feeding a support from a first film roll, forming,
on the support, a coating film having a degree of hardness of 3B or
more, and winding up the support into a second film roll at a
tension of 30 N/m or more; and loading the second film roll which
has been wound up in the prior step in a vacuum film forming
apparatus, continuously feeding the support from the second film
roll, forming an inorganic film on the coating film formed on the
support, and winding up the support into a third film roll.
Inventors: |
Iwase; Eijirou; (Kanagawa,
JP) ; Fujinawa; Jun; (Kanagawa, JP) |
Correspondence
Address: |
YOUNG & THOMPSON
209 Madison Street, Suite 500
Alexandria
VA
22314
US
|
Assignee: |
FUJIFILM CORPORATION
Tokyo
JP
|
Family ID: |
43124759 |
Appl. No.: |
12/782204 |
Filed: |
May 18, 2010 |
Current U.S.
Class: |
428/688 ; 118/33;
427/172 |
Current CPC
Class: |
B05D 2502/00 20130101;
C23C 14/562 20130101; B05D 7/04 20130101; C23C 16/545 20130101;
B05D 3/067 20130101; B05D 2252/02 20130101 |
Class at
Publication: |
428/688 ;
427/172; 118/33 |
International
Class: |
B32B 9/00 20060101
B32B009/00; B05D 1/36 20060101 B05D001/36; B05C 13/00 20060101
B05C013/00 |
Foreign Application Data
Date |
Code |
Application Number |
May 20, 2009 |
JP |
2009-122136 |
Claims
1. A method for manufacturing a functional film, comprising the
steps of: continuously feeding a support from a first film roll,
forming, on the support, a coating film having a degree of hardness
of 3B or more, and winding up the support into a second film roll
at a tension of 30 N/m or more; and loading the second film roll
which has been wound up in the prior step in a vacuum film forming
apparatus, continuously feeding the support from the second film
roll, forming an inorganic film on the coating film formed on the
support, and winding up the support into a third film roll.
2. The method for manufacturing a functional film according to
claim 1, wherein the support having the coating film formed thereon
is wound up into the second film roll by using a lay-on roller.
3. The method for manufacturing a functional film according to
claim 1, wherein the thickness of the inorganic film formed is 10
nm or more.
4. The method for manufacturing a functional film according to
claim 1, wherein the coating film is formed of a material
comprising a radiation-curable monomer or oligomer.
5. A functional film, manufactured by the method according to claim
1.
6. An apparatus for manufacturing a functional film, comprising: a
coating film forming apparatus; and a vacuum film forming
apparatus, the coating film forming apparatus comprising: a
mechanism for continuously feeding a support from a first film
roll; a mechanism for forming a coating film having a degree of
hardness of 3B or more on the support; and a mechanism for winding
up the support into a second film roll at a tension of 30 N/m or
more, and the vacuum film forming apparatus comprising: a mechanism
for continuously feeding the support from the second film roll
which has been wound up by the coating film forming apparatus; a
mechanism for forming an inorganic film on the coating film formed
on the support; and a mechanism for winding up the support into a
third film roll.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the priority benefit under 35 U.S.C.
.sctn.119 of Japanese Patent Application No. 2009-122136 filed on
May 20, 2009, which is hereby incorporated in its entirety by
reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The presently disclosed subject matter relates to a
functional film, a method for manufacturing the functional film,
and an apparatus for manufacturing the functional film, and more
specifically, to a functional film including a laminated structure,
in which an inorganic film is formed on a coating film that has
been formed while feeding a film roll obtained by winding the
formed coating film; a method for manufacturing the functional
film, and an apparatus for manufacturing the functional film.
[0004] 2. Description of the Related Art
[0005] Functional films such as gas barrier films, protective
films, optical filters, and anti-reflection films are used in a
variety of devices, for example, optical elements, display
apparatuses such as liquid crystal display apparatuses, and organic
EL (electroluminescence) display apparatuses; semiconductor
apparatuses; and thin-film solar cells.
[0006] Meanwhile, for manufacturing these functional films, film
formation techniques through vacuum film forming methods such as
sputtering, and plasma CVD (chemical vapor deposition) method are
used. In order to efficiently form a film by a vacuum film forming
method while achieving high productivity, it is carried out to
continuously form a film on a lengthy base material.
[0007] The following describes one method for manufacturing the
above-mentioned functional film. A lengthy support is continuously
fed from a film roll. Then, a coating liquid is applied onto the
support, dried, and cured to form a coating film. The support
having the coating film formed thereon is wound up to form a film
roll. Next, the film roll having the coating film formed thereon is
set in a feeding unit of a vacuum film forming apparatus, and the
support is continuously fed from the film roll to a film formation
chamber. Then, in the film formation chamber, an inorganic film is
formed on the coating film to form a film having a laminated
structure composed of the coating film and the inorganic film, and
the film having a laminated structure is wound up, thereby
manufacturing a film roll. As equipment for carrying out such a
film forming method, a so-called roll-to-roll film forming
apparatus is known. By repeating the step of forming a coating film
and an inorganic film plural times by the film forming apparatus,
it is possible to manufacture a functional film having a plurality
of laminated structures formed.
[0008] In the above manufacturing method, in order to prevent
winding faults during film formation of an inorganic film (rub
between the inorganic film formed on a support caused by winding
the support) and to maintain uniform quality of a functional film,
Japanese Patent Application Laid-Open No. 08-92727 discloses a
method in which a film roll having a winding hardness (hardness of
the film roll) of 70 to 95 is set in a feeding unit of a vacuum
film forming apparatus, and an inorganic film is continuously
formed on a support.
SUMMARY OF THE INVENTION
[0009] However, even if a film roll having a coating film formed
thereon is wound with a winding hardness of 70 to 95 as described
in Japanese Patent Application Laid-Open No. 08-92727, the film
roll unfavorably picks up entrained air when the support is wound
up. When an air-entrained film roll is set in a feeding unit in a
vacuum film forming apparatus, the pressure around the feeding unit
being reduced; the entrained air in the film roll comes out of the
film roll. Thus, the balance of stress (tension, frictional force)
inside the film roll is disrupted while the stress is balanced
during winding the film. The film roll tends to cause "tight
winding" (shrinkage of roll diameter).
[0010] The inventors of the presently disclosed subject matter have
found that if a film roll causes the "tight winding", in the film
roll, a coating film formed on a support comes into contact with a
back surface of the support which is thereabove, and microscopic
film rupture occurs in the coating film, resulting in loss of
smoothness of the film.
[0011] Subsequently, when the support is conveyed and an inorganic
film is formed on the coating film, a film-forming fault occurs to
cause cracks and peel-off of the inorganic film.
[0012] The presently disclosed subject matter has been made in
light of the circumstances, and an object of the presently
disclosed subject matter is to provide a functional film, a method
for manufacturing the functional film and an apparatus for
manufacturing the functional film capable of reducing the
occurrence of faults such as cracks and peel-off of an inorganic
film when the inorganic film is formed on a coating film by a
vacuum film forming method.
[0013] To achieve the above-mentioned object, the presently
disclosed subject matter provides a method for manufacturing a
functional film includes the steps of: continuously feeding a
support from a first film roll, forming, on the support, a coating
film having a degree of hardness of 3B or more, and winding up the
support into a second film roll at a tension of 30 N/m or more; and
loading the second film roll which has been wound up in the prior
step in a vacuum film forming apparatus, continuously feeding the
support from the second film roll, forming an inorganic film on the
coating film formed on the support, and winding up the support into
a third film roll. Here, the hardness is represented by the pencil
hardness defined by the Japanese Industrial Standards, no. JIS S
6006.
[0014] According to the presently disclosed subject matter, even
when the second film roll which is obtained by coating, drying and
curing a coating film having a degree of hardness of 3B or more and
then winding at a tension of 30 N/m or more is set in a vacuum film
forming apparatus, the coating film will not suffer damage, and
thus it is possible to provide a method for manufacturing a
functional film capable of reducing the occurrence of faults such
as cracks and peel-off of a coating film and an inorganic film.
[0015] Note that the degree of hardness of the coating film is more
preferably 3B to 3H and the tension at which the coating film is
wound up on the second film roll is more preferably 30 N/m to 500
N/m.
[0016] In the method for manufacturing a functional film of the
presently disclosed subject matter, in order to wind up the support
having the coating film formed thereon into the second film roll,
it is preferably to wind up the support using a lay-on roller.
[0017] By using a lay-on roller, it is possible to reduce entrained
air from getting inside the second film roll during winding, and
thus even when the second film roll of the support having the
coating film formed thereon is loaded in the vacuum film forming
apparatus, it is possible to reduce the occurrence of tight
winding.
[0018] Further, in the method for manufacturing a functional film
of the presently disclosed subject matter, the thickness of the
inorganic film formed is preferably 10 nm or more. Note that, the
thickness of the inorganic film is more preferably 10 nm to 200
nm.
[0019] Further, in the method for manufacturing a functional film
of the presently disclosed subject matter, the coating film is
preferably formed of a material containing a radiation-curable
monomer or oligomer.
[0020] When the coating film is formed of a material containing a
radiation-curable monomer or oligomer, the presently disclosed
subject matter is greatly effective.
[0021] In order to achieve the above-mentioned object, the
functional film of the presently disclosed subject matter is a
functional film manufactured by the manufacturing method described
above.
[0022] In a function film manufactured by the manufacturing method
of the presently disclosed subject matter, faults such as cracks
and peel-off of an inorganic film are reduced, and thus the
functional film can be suitably used as various functional films
for use in optical elements, display apparatuses, semiconductor
apparatuses, thin film solar cells and the like.
[0023] An apparatus for producing a functional film according to an
aspect of the presently disclosed subject matter includes a coating
film forming apparatus; and a vacuum film forming apparatus, the
coating film forming apparatus including: a mechanism for
continuously feeding a support from a first film roll; a mechanism
for forming a coating film having a degree of hardness of 3B or
more on the support; and a mechanism for winding up the support
into a second film roll at a tension of 30 N/m or more, and the
vacuum film forming apparatus including: a mechanism for
continuously feeding the support from the second film roll which
has been wound up by the coating film forming apparatus; a
mechanism for forming an inorganic film on the coating film formed
on the support; and a mechanism for winding up the support into a
third film roll.
[0024] According to the presently disclosed subject matter, it is
possible to provide a functional film, a method for manufacturing
the functional film, and an apparatus for manufacturing the
functional film capable of reducing the occurrence of faults such
as cracks and peel-off of an inorganic film due to impairment of
the smoothness of a coating film when an inorganic film is formed
on the coating film by a vacuum film forming method.
BRIEF DESCRIPTION OF THE DRAWINGS
[0025] FIG. 1 is a diagram for illustrating a functional film
manufactured by a method for manufacturing a functional film
according to the presently disclosed subject matter;
[0026] FIGS. 2A and 2B are diagrams for illustrating an example of
an apparatus for implementing a method for manufacturing a
functional film according to the presently disclosed subject
matter; and
[0027] FIG. 3 is a diagram for illustrating a preferred embodiment
of a mechanism for winding a film roll.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0028] Hereinafter, preferred embodiments of the presently
disclosed subject matter will be described according to the
drawings. The presently disclosed subject matter will be described
through the following preferred embodiments, many modifications can
be made without departing from the scope of the presently disclosed
subject matter and other embodiments other than the above
embodiments can be used. Accordingly, all modifications within the
scope of the presently disclosed subject matter are included within
the spirit and scope of the appended claims. Also, a numerical
range designated as "A to B" means being more than or equal to A
and less than or equal to B in the presently disclosed subject
matter.
[0029] The following describes a method for manufacturing a
functional film of the presently disclosed subject matter.
[0030] FIG. 1 illustrates a conceptual diagram of a functional film
manufactured by a method for manufacturing a functional film of the
presently disclosed subject matter.
[0031] As illustrated in FIG. 1, in the method for manufacturing a
functional film, a predetermined coating film 12 is formed on a
surface of a support B (raw fabric film), and an inorganic film 14
is formed on the coating film 12 by a vacuum film forming method to
manufacture a laminate 10 (hereinbelow, otherwise referred to as a
functional film, laminated film or optical film).
[0032] By way of an example, the method for manufacturing a
functional film is a method in which a laminated film 10 is
manufactured by a coating film forming apparatus 20 which forms a
coating film 12 on a surface of the support B and by a vacuum film
forming apparatus 22 which forms an inorganic film 14 on a surface
of the coating film 12.
[0033] FIG. 2A conceptually illustrates an example of the coating
film forming apparatus 20 for implementing the method for
manufacturing a functional film.
[0034] The coating film forming apparatus 20 includes a coating
device 26, a heating device 28 and a UV (ultraviolet) irradiation
device 30, in which a previously prepared coating liquid containing
a radiation-curable monomer or a radiation-curable oligomer is
applied onto a support B by the coating device 26, dried by the
heating device 28 and polymerized by the UV irradiation device 30,
thereby forming a coating film 12.
[0035] This coating film forming apparatus 20 forms a coating film
by a roll-to-roll process. A support B is loaded, as a film roll
40, on a rotating shaft 32, and a coating film is formed on the
support B while the support B is conveyed in a longitudinal
direction thereof. A support Bo on which the coating film has been
formed is wound up as a film roll 42 by a wind-up shaft 34.
[0036] The support B fed from the film roll 40 is first conveyed to
the coating device 26. In the coating device 26, a previously
prepared coating liquid containing the radiation-curable monomer or
oligomer, which will become the coating film 12, is applied to a
surface of the support B. For the application of the coating
liquid, any ordinary liquid coating methods can be employed.
[0037] The support B is next conveyed to the heating device 28. In
the heating device 28, a solvent in the coating liquid that has
been applied by the coating device 26 is dried before the support B
reaches the UV irradiation device 30. The heating method of the
coating liquid is not particularly limited, and any known heating
devices, such as heating by a heater and heating by hot air flow,
can be employed, as long as the coating liquid can be heated in
accordance with the conveying speed of the support B, before the
support B reaches the UV irradiation device 30.
[0038] The support B is next conveyed to the UV irradiation device
30. In the UV irradiation device 30, the coating liquid that has
been applied by the coating device 26 and heated and dried by the
heating device 28 is irradiated with ultraviolet rays so as to
polymerize the radiation-curable monomer or oligomer, thereby
forming the coating film 12.
[0039] In the presently disclosed subject matter, the coating film
is formed so as to have a degree of hardness of 3B or more. The
degree of hardness of the coating film is adjusted so that the
pencil hardness thereof is 3B or more by controlling the exposure
dose of ultraviolet ray through varying the intensity of
illumination or the conveying speed. Here, the pencil hardness is
defined by the Japanese Industrial Standards, no. JIS S 6006.
[0040] Further, in the presently disclosed subject matter, the
support Bo is wound up as a film roll 42 at a tension of 30 N/m or
more.
[0041] Even when a film roll 42 obtained by coating, drying, and
curing a coating film having a degree of hardness of 3B or more and
winding at a tension of 30 N/m or more is set in the
after-mentioned vacuum film forming apparatus 22, the resulting
coating film will not suffer damage, and thus it is possible to
reduce the occurrence of faults such as cracks and peel-off of an
inorganic film.
[0042] FIG. 3 is a schematic diagram illustrating a preferred
mechanism for winding up a film roll according to the presently
disclosed subject matter.
[0043] A roll core is set at the wind-up shaft 34 and is driven to
rotate by a motor (not illustrated). Then, the support Bo is wound
up to become the film roll 42.
[0044] In the mechanism illustrated in FIG. 3, a lay-on roller 90
is rotatably mounted so as to rotate in contact with the film roll
42. This lay-on roller 90 is adapted to press the support Bo toward
the roll core by a pressing mechanism 92. With this configuration,
it is possible to remove air entrained with the support Bo during
winding the support Bo and to form a film roll 42 where air trapped
between the surfaces of the support Bo is removed.
[0045] That is, by using the lay-on roller, entrained air generated
during winding the support Bo can be reduced, and thus even when a
film roll of the support having a coating film formed thereon is
loaded in a vacuum film forming apparatus, it is possible to reduce
the occurrence of tight winding of the coating film.
[0046] Next, the film roll 42 obtained by winding the support Bo
having the coating film 12 formed thereon is loaded in a vacuum
film forming apparatus 22 as conceptually illustrated in FIG.
2B.
[0047] The vacuum film forming apparatus 22 forms an inorganic film
14 on a surface of the support Bo (i.e., a surface of the coating
film 12) by a vacuum film forming method. The vacuum film forming
apparatus 22 includes a supply chamber 50, a film formation chamber
52, and a wind-up chamber 54.
[0048] Similarly to the coating film forming apparatus 20, the
vacuum film forming apparatus 22 is also an apparatus that forms a
film by a roll-to-roll process. In the vacuum film forming
apparatus 22, the support Bo is fed from the film roll 42, and an
inorganic film 14 is formed on the support Bo while the support Bo
is conveyed in a longitudinal direction. A functional film 10 on
which the coating film 12 and the inorganic film 14 have been
formed is wound up in the form of a roll by a wind-up shaft 58.
[0049] The supply chamber 50 includes a rotating shaft 56, a guide
roller (path roller) 60 and a vacuum evacuation device 61.
[0050] In the vacuum film forming apparatus 22, the film roll 42
obtained by winding the support Bo, in which the coating film 12
has been formed on the support B, is loaded on a rotating shaft 56
in the supply chamber 50. When film roll 42 is loaded on the
rotating shaft 56, the support Bo is passed along a predetermined
conveying path from the supply chamber 50, via the film formation
chamber 52, to the wind-up shaft 58 in the wind-up chamber 54.
Also, in the vacuum film forming apparatus 22, feeding of the
support Bo from the film roll 42 is performed in synchronization
with winding the functional film 10 by the rotating shaft 56, and
while the lengthy support Bo is conveyed in its longitudinal
direction in the predetermined conveying path, film formation of
the inorganic film 14 is continuously performed on the support
Bo.
[0051] In the supply chamber 50, the rotating shaft 56 is driven to
rotate in a clockwise direction in the figure by a drive source
(not illustrated), whereby the support Bo is fed from the film roll
42, guided along the predetermined path by a guide roller (path
roller) 60, and fed to the film formation chamber 52.
[0052] Meanwhile, on the supply chamber 50, the vacuum evacuation
device 61 is placed, and the pressure inside the supply chamber 50
is reduced to a predetermined degree of vacuum (pressure) according
to the film formation pressure in the film formation chamber 52,
thereby preventing the pressure in the supply chamber 50 from
adversely affecting the pressure in the film formation chamber 52
and the film formation. Note that as the vacuum evacuation device
61, a known vacuum evacuation device can be used, similarly to the
after-mentioned vacuum evacuation device 72 which is placed at the
film formation chamber 52.
[0053] Further, the supply chamber 50 may include, in addition to
the illustrated members, various members (conveying devices) for
conveying the support Bo along the predetermined path, such as a
pair of conveying rollers, and guide members for regulating a
position of the support Bo in a cross-machine direction.
[0054] The support Bo is guided by the guide roller 60 and conveyed
to the film formation chamber 52.
[0055] The film formation chamber 52 is provided for forming the
inorganic film 14 on a surface of the support Bo (i.e., on a
surface of the coating film 12) by a vacuum film forming method. In
the illustrated example, the film formation chamber 52 includes a
drum 62, film forming devices 64a, 64b, 64c, and 64d, guide rollers
68 and 70, and a vacuum evacuation device 72. Note that when the
film formation chamber 52 is the one where film formation is
performed by sputtering, plasma CVD or the like, a high-frequency
power source and the like are further provided in the film
formation chamber 52.
[0056] The support Bo is conveyed to the film formation chamber 52
from a slit 74a formed in a partition wall 74 which separates the
supply chamber 50 from the film formation chamber 52.
[0057] Notably, in the illustrated example of the vacuum film
forming apparatus 22, a vacuum evacuation device is preferably
provided in the supply chamber 50 as well as in the wind-up chamber
54, and the inside of the supply chamber 50 and the wind-up chamber
54 are also evacuated to a vacuum state in accordance with the film
formation pressure at the film formation chamber 52. The apparatus
for implementing the presently disclosed subject matter is not
limited to the illustrated example. For example, the apparatus may
be configured so that no vacuum evacuation device is provided in
the supply chamber 50 and in the wind-up chamber 54, and the slits
through which the support Bo passes may be formed to have such a
minimum size that the support Bo can pass through without
contacting the support Bo, whereby the film formation chamber 52 is
configured to be substantially airtight. Alternatively, the
apparatus may be configured so that no vacuum evacuation device is
provided in the supply chamber 50 and in the wind-up chamber 54,
and a sub-chamber through which the support Bo passes is provided
between the supply chamber 50 and film formation chamber 52, and
between the film formation chamber 52 and the wind-up chamber 54,
the inside of each of the sub-chambers may be vacuumized by a
vacuum pump.
[0058] Note that when a sub-chamber or the like is provided
upstream the film formation chamber 52 (upstream in the conveyance
direction of the support Bo), it is required that a device for
conveying the base material inside the sub-chamber, if the device
comes into contact with the coating film 12, be also configured to
be in contact with only the ends of the support Bo.
[0059] The drum 62 in the film formation chamber 52 is a
cylindrical member which rotates in a counterclockwise direction in
the figure, on the basis of the center line thereof.
[0060] The support Bo supplied from the supply chamber 50 and
guided to the predetermined path by the guide roller (path roller)
68 is spooled over the drum 62 and is conveyed along the
predetermined conveyance path while being supported and guided by
the drum 62, and then the inorganic film 14 is formed on its
surface (on the coating film 12) by the film forming devices 64a to
64d and the like. When in the film formation chamber 52, film
formation is performed by sputtering, plasma CVD or the like, the
drum 62 may be grounded (earthed) or connected to a high-frequency
power source so as to function as a counter-electrode.
[0061] The film forming devices 64a to 64d are provided for forming
the inorganic film 14 over the surface of the support B by a vacuum
film forming method.
[0062] Here, in the manufacturing method of the presently disclosed
subject matter, the forming method of the inorganic film 14 is not
particularly limited, and any known vacuum film forming methods
(vapor-phase deposition methods) such as CVD, plasma CVD,
sputtering, vacuum deposition, and ion-plating can be employed.
[0063] Thus, the film forming devices 64a to 64d are composed of
various members suitable for the vacuum film forming method
implemented.
[0064] For example, when the film formation chamber 52 is the one
where the inorganic film 14 is formed by an ICP-CVD method
(Inductively-Coupled Plasma CVD), the film forming devices 64a to
64d can include an induction coil for forming an induction magnetic
field, and a gas supply device for supplying a film formation area
with a reactive gas.
[0065] When the film formation chamber 52 is the one where the
inorganic film 14 is formed by a CCP-CVD method
(Capacitively-Coupled Plasma CVD), the film forming devices 64a to
64d can include a shower electrode which is a hollow shaped member
having a number of micro pores at the surface facing the drum 62
and functions as a high-frequency electrode and a reactive gas
supplying device to be connected to a reactive gas supply
source.
[0066] When the film formation chamber 52 is the one where the
inorganic film 14 is formed by a CVD method, the film forming
devices 64a to 64d can include a device for introducing a reactive
gas.
[0067] In addition, when the film formation chamber 52 is the one
where the inorganic film 14 is formed by sputtering, the film
forming devices 64a to 64d can include a device for holding a
target, a high-frequency electrode, and a device for supplying a
sputtering gas.
[0068] The vacuum evacuation device 72 evaluates the film formation
chamber 52 to a degree of vacuum adequate for the formation of the
inorganic film 14 by a vacuum film forming method.
[0069] The vacuum evacuation device 72 is not also particularly
limited. A known (vacuum) evacuation device which is employed in a
vacuum film forming apparatus can be used as the vacuum evacuation
device 72. The known (vacuum) evacuation device can be a vacuum
pump such as a turbo pump, a mechanical booster pump and a rotary
pump. The known (vacuum) evacuation device can include a device
which uses an auxiliary device such as cryocoil, and a device for
adjusting the ultimate degree of vacuum or the discharge air
amount.
[0070] While being supported and conveyed by the drum 62, the
support Bo having on its surface the inorganic film 14 formed by
the film forming devices 64a to 64d, that is, the functional film
10 is guided to a predetermined path by the guide roller 70,
conveyed to the wind-up chamber 54 and wound up in the form of a
roll by the wind-up shaft 58. The laminated film (functional film)
roll wound up in the form of a roll is then subjected to the
subsequent step.
[0071] As described above, the method for manufacturing a
functional film of the presently disclosed subject matter includes
the steps of: continuously feeding a support B from a film roll 40,
forming, on the support B, a coating film 12 having a degree of
hardness of 3B (indicated by the pencil hardness) or more, and
winding up the support B into a film roll 42 at a tension of 30 N/m
or more; and loading the film roll 42 which has been wound up in
the prior step in a vacuum film forming apparatus 22, continuously
feeding the support Bo from the film roll 42, forming an inorganic
film 14 on the coating film 12 formed on the support Bo, and
winding up the support Bo into a film roll.
[0072] According to a conventional method for manufacturing a
functional film, when a film roll 42 entrained with air is set in a
feeding unit in a depressurized vacuum film forming apparatus 22,
the entrained air in the film roll comes out of the film roll,
whereby the balance of stress (tension, frictional force) inside
the film roll is disrupted while the stress is balanced during
winding the functional film, causing "tight winding" of the film
roll. Then, the inventors of the presently disclosed subject matter
found that when the "tight winding" occurs, in the film roll, a
coating film formed on a support comes into contact with a back
surface of the support present in its upper position, microscopic
film rupture occurs in the coating film, resulting in a lost of
smoothness of the film. Thereafter, when the support is conveyed
and an inorganic film is formed on the coating film, a film-forming
fault occurs to cause cracks and peel-off of the inorganic
film.
[0073] Then, the inventors of the presently disclosed subject
matter have derived optimum conditions for the degree of hardness
of the coating film and the tension applied to the support during
winding the support. And, the present inventors of the presently
disclosed subject matter have found that it is important to wind
the support under the optimum conditions.
[0074] According to the presently disclosed subject matter, even
when a film roll which is obtained by coating, drying and curing a
coating film having a degree of hardness of 3B (pencil hardness) or
more and then winding at a tension of 30 N/m or more is set in a
vacuum film forming apparatus, the coating film will not suffer
damage. Therefore, according to the presently disclosed subject
matter, it is possible to provide a method for manufacturing a
functional film capable of reducing the occurrence of faults such
as cracks and peel-off of an inorganic film.
[0075] Note that the degree of hardness of the coating film is more
preferably 3B to 3H (pencil hardness) and the tension at which the
coating film is wound up on the film roll is more preferably 30 N/m
to 500 N/m.
[0076] Meanwhile, in the presently disclosed subject matter, the
thickness of the inorganic film 14 formed is preferably 10 nm or
more. More specifically, the thickness of the inorganic film is
more preferably 10 nm to 200 nm.
[0077] By the method for manufacturing a functional film of the
presently disclosed subject matter, it is possible to reduce the
occurrence of faults such as cracks and peel-off of an inorganic
film. Thus, the presently disclosed subject matter can provide a
high-yield method for manufacturing a functional film.
[0078] The coating film 12 preferably has a smooth surface and a
high degree of film hardness. The smoothness of the coating film 12
is, as a surface roughness (Ra value) in an area of 10-.mu.m
square, preferably 10 nm or less, more preferably 2 nm or less.
[0079] In the presently disclosed subject matter, the support B
over which the coating film 12 and inorganic film 14 will be formed
is not particularly limited. Any various base materials (base
films) used for various types of functional films such as a gas
barrier film, an optical film and a protective film, can be used as
the support B, as long as the base materials are the
after-mentioned materials capable of forming the coating film 12
and forming the inorganic film 14 through vacuum film forming. For
example, various types of resin films such as PET (polyethylene
terephthalate) film, and various types of metal sheets such as
aluminum sheet can be used as the support B.
[0080] Further, the support B may be the one having, on its
surface, various types of formed films such as a protective film
and an adhesive film.
[0081] The coating film 12 can contain, as the main component, a
radiation-curable monomer or a radiation-curable oligomer. More
specifically, as the monomer or oligomer to be used, preferred are
monomers or oligomers which have two or more ethylenically
unsaturated double bonds and which are addition polymerizable by
irradiation with light. As such monomers or oligomers, there may be
exemplified a compound having at least one addition-polymerizable
ethylenically unsaturated group in the molecule and having a
boiling point of 100.degree. C. or higher under normal pressure.
Specific examples thereof include monofunctional acrylates and
monofunctional methacrylates such as polyethylene glycol
mono(meth)acrylate, polypropylene glycol mono(meth)acrylate, and
phenoxyethyl(meth)acrylate; polyethylene glycol di(meth)acrylate,
polypropylene glycol di(meth)acrylate, trimethylolethane
triacrylate, trimethylolpropane tri(meth)acrylate,
trimethylolpropane diacrylate, neopentyl glycol di(meth)acrylate,
pentaerythritol tetra(meth)acrylate, pentaerythritol
tri(meth)acrylate, dipentaerythritol hexa(meth)acrylate,
dipentaerythritol penta(meth)acrylate, hexanediol di(meth)acrylate,
trimethylolpropane tri(acryloyloxypropyl) ether,
tri(acryloyloxyethyl) isocyanurate, tri(acryloyloxyethyl)
cyanurate, and glycerin tri(meth)acrylate; and polyfunctional
acrylates and polyfunctional methacrylates, for example, those
obtained by addition of an ethylene oxide or propylene oxide on a
polyfunctional alcohol, such as trimethylolpropane and glycerin,
followed by subjecting to (meth)acrylation.
[0082] In addition to the above, there may be exemplified urethane
acrylates described in Japanese Examined Application Publication
Nos. 48-41708, 50-6034 and Japanese Patent Application Laid-Open
No. 51-37193; polyester acrylates described in Japanese Patent
Application Laid-Open No. 48-64183, Japanese Examined Application
Publication Nos. 49-43191 and 52-30490; and polyfunctional
acrylates and methacrylates such as epoxy acrylates, which are
reaction products between an epoxy resin and a (meth)acrylic
acid.
[0083] Among these, preferred are trimethylolpropane
tri(meth)acrylate, pentaerythritol tetra(meth)acrylate,
dipentaerythritol hexa(meth)acrylate, and dipentaerythritol
penta(meth)acrylate.
[0084] Besides the above, as preferred examples thereof,
"polymerizable compound B" described in Japanese Patent Application
Laid-Open No. 11-133600 may be exemplified as well.
[0085] As a photopolymerization initiator or photopolymerization
initiator system to be used, there may be exemplified a vicinal
polyketaldonyl compound disclosed in U.S. Pat. No. 2,367,660, an
acyloin ether compound described in U.S. Pat. No. 2,448,828, an
aromatic acyloin compound substituted with .alpha.-hydrocarbon
described in U.S. Pat. No. 2,722,512, a polynuclear quinone
compound described in U.S. Pat. Nos. 3,046,127 and 2,951,758, a
combination of a triarylimidazole dimer and p-aminoketone described
in U.S. Pat. No. 3,549,367, a benzothiazole compound and a
trihalomethyl-s-triazine compound described in Japanese Examined
Application Publication No. 51-48516, a trihalomethyl-triazine
compound described in U.S. Pat. No. 4,239,850, and a
trihalomethyloxadiazole compound described in U.S. Pat. No.
4,212,976. Particularly, trihalomethyl-s-triazine,
trihalomethyloxadiazole, and triarylimidazole dimer are
preferred.
[0086] Additionally, preferred examples thereof include a
"polymerization initiator C" described in Japanese Patent
Application Laid-Open No. 11-133600. The amount of the
photopolymerization initiator used is preferably 0.01% by mass to
20% by mass, more preferably 0.5% by mass to 10% by mass relative
to the solid content of the coating liquid. As for the irradiation
of light for the polymerization of a liquid crystal compound, it is
preferred to use ultraviolet ray. The radiation energy of the
ultraviolet ray is preferably 20 mJ/cm.sup.2 to 50 J/cm.sup.2, more
preferably 100 mJ/cm.sup.2 to 2,000 mJ/cm.sup.2. In order to
accelerate the photopolymerization reaction, the irradiation of
light may be performed under heating conditions.
[0087] Examples of the forming method of the coating film 12
include a usual solution coating method, or a vacuum film forming
method.
[0088] As the solution coating method, the coating liquid can be
applied by using, for instance, a dip coating method, an air knife
coating method, a curtain coating method, a roller coating method,
a wire-bar coating method, a gravure coating method, a slide
coating method, or an extrusion coating method using a hopper
described in U.S. Pat. No. 2,681,294.
[0089] Note that acrylate and methacrylate suffer from
polymerization inhibition due to oxygen in air. For this reason, in
the presently disclosed subject matter, when acrylate and/or
methacrylate are used as the coating film 12, it is preferable to
reduce the oxygen concentration or the oxygen partial pressure
during the polymerization. When the oxygen concentration during the
polymerization is reduced by nitrogen substitution, the oxygen
concentration is preferably 2% or less, more preferably 0.5% or
less. When the oxygen partial pressure during the polymerization is
reduced by depressurization, the total pressure is preferably 1,000
Pa or less, more preferably 100 Pa or less. It is particularly
preferred to perform the polymerization by irradiating with
ultraviolet ray under the conditions of a reduced pressure of 100
Pa or less and a radiation energy of 2 J/cm.sup.2 or more.
[0090] In the presently disclosed subject matter, the degree of
polymerization of the monomer is preferably 80% or more, more
preferably 85% or more, still more preferably 90% or more. The
degree of polymerization mentioned here means a ratio of the
reacted polymerizable groups to all the polymerizable groups (for
example, in the case of using acrylate and/or methacrylate,
acryloyl groups and/or methacryloyl groups) in the monomer
mixture.
[0091] When as a laminated film (functional film), a protective
film for various devices and systems, such as display apparatuses
like an organic EL display apparatus and a liquid crystal display
apparatus, is manufactured, a silicon oxide film may be formed as
the inorganic film 14.
[0092] Further, when an optical film such as an anti-reflection
film, a light reflection film or various filters is manufactured, a
film made of a material having or exhibiting intended optical
properties may be formed as an inorganic film 14.
[0093] Among these films, the manufacturing method of the presently
disclosed subject matter is most suitable for manufacturing a gas
barrier film because an inorganic film 14 excellent in gas barrier
property can be formed owing to its excellent surface smoothness of
the coating film 12.
[0094] In lamination process, i.e., when a coating film is further
formed on the inorganic film, "tight winding" and "handling damage"
can occur, and thus the effects of the presently disclosed subject
matter are greatly exhibited.
[0095] Hereinabove, a functional film, a method for manufacturing
the functional film, and an apparatus for manufacturing the
functional film according to the presently disclosed subject matter
have been described in detail through the embodiments, which
however shall not be construed as limiting the scope of the
presently disclosed subject matter. Accordingly various
modifications and equivalent arrangements may be made without
deviating from the spirit and scope of the presently disclosed
subject matter.
EXAMPLES
[0096] Hereinafter, the presently disclosed subject matter will be
further described in detail with reference to certain specific
examples of the presently disclosed subject matter.
Example 1
[0097] A functional film was manufactured using a coating film
forming apparatus 20 and a vacuum film forming apparatus 22
illustrated in FIG. 2.
[0098] The coating film 12 was formed in the following manner. An
acrylic monomer and a photopolymerization initiator were dissolved
in an organic solvent to prepare a coating solution, and the
coating solution was applied to a support B by a die coater, dried
and then cured by ultraviolet curing to form a coating film. The
thickness of the coating film was controlled with a liquid feeding
rate so that the coating film had a thickness of 1 .mu.m in a
completely cured state. The degree of hardness of the coating film
was adjusted by controlling the exposure dose of ultraviolet ray
through varying the intensity of illumination or the conveying
speed, thereby providing a desired film hardness (pencil hardness)
described in Table 1.
[0099] As the support B, a PET base of 1,000 mm in width and 100
.mu.m in thickness was used.
[0100] In a winder used, the winding-up tension was controlled so
as to be constant at a value described in Table 1, depending on the
winding diameter.
[0101] As an inorganic film 14, an alumina film was formed by
reactive sputtering using aluminum as a target, thereby obtaining a
functional film 10 having a desired thickness described in Table
1.
[0102] The thus manufactured functional film 10 was subjected to an
evaluation for the water vapor permeability performance according
to the following evaluation criteria.
[Evaluation Criteria of Performance (Water Vapor Permeability)]
[0103] D: 1.0.times.10.sup.-3 g/m.sup.2day or more [0104] C:
2.0.times.10.sup.-4 g/m.sup.2day or more and less than
1.0.times.10.sup.-3 g/m.sup.2day [0105] B: 1.0.times.10.sup.-4
g/m.sup.2day or more and less than 2.0.times.10.sup.-4 g/m.sup.2day
[0106] A: less than 1.0.times.10.sup.-4 g/m.sup.2day
TABLE-US-00001 [0106] TABLE 1 Degree of hardness of Winding-up
organic film Thickness Water vapor tension (pencil of inorganic
permeability Evaluation of Experiment (N/m) hardness) film (nm)
(g/m.sup.2 day) performance 1 30 4B 60 3.4 .times. 10.sup.-3 D 2
150 4B 60 3.1 .times. 10.sup.-3 D 3 500 4B 60 1.8 .times. 10.sup.-3
D 4 10 3B 60 2.8 .times. 10.sup.-3 D 5 30 3B 60 3.7 .times.
10.sup.-4 C 6 150 3B 60 1.9 .times. 10.sup.-4 B 7 500 3B 60 1.7
.times. 10.sup.-4 B 8 150 B 60 1.4 .times. 10.sup.-4 B 9 150 H 60
9.5 .times. 10.sup.-5 A 10 150 3H 60 8.9 .times. 10.sup.-5 A 11 150
3B 10 3.2 .times. 10.sup.-4 C 12 150 3B 200 1.2 .times. 10.sup.-4
B
[0107] As understood from Table 1, the functional film, which has
been manufactured so that the degree of hardness of a coating film
is 3B (pencil hardness) or more and the winding-up tension is kept
at 30 N/m or more, can be improved in the performance of water
vapor permeability. Consequently, the occurrence of faults such as
cracks and peel-off of an inorganic film can be reduced by the
presently disclosed subject matter.
Example 2
[0108] A functional film was manufactured using a coating film
forming apparatus 20 and a vacuum film forming apparatus 22
illustrated in FIG. 2.
[0109] As material of the coating film 12, a coating liquid was
prepared in which VYLON 245 (2 parts) was dissolved in MEK (methyl
ethyl ketone) (40 parts) and cyclohexanone (60 parts). Here, VYLON
is a registered trademark in Japan, and VYLON 245 is a product (a
kind of amorphous polyester resin (organic solvent fusible type))
of Toyobo Co., Ltd.
[0110] As a support B, a PEN (polyethylene naphthalate) film of
1,000 mm in width and 100 .mu.m in thickness was used. The prepared
coating liquid was applied onto the PEN film by a bar coater, and
dried, to thereby form a coating film on the PEN film.
[0111] In a wind-up chamber, the PEN film was wound up into a film
roll by a wind-up shaft so that the winding-up tension was kept
constant (150 N/m) depending on the winding diameter.
[0112] In a winder used, the winding-up tension was controlled so
as to be constant at a value described in Table 2, depending on the
winding diameter.
[0113] As an inorganic film 14, a SiO film was formed by reactive
sputtering, thereby obtaining a functional film 10 having a desired
thickness described in Table 2.
[0114] The thus manufactured functional film 10 was subjected to an
evaluation for the water vapor permeability performance according
to the following evaluation criteria.
[Evaluation Criteria of Performance (Water Vapor Permeability)]
[0115] D: 1.0.times.10.sup.-1 g/m.sup.2day or more [0116] C:
2.0.times.10.sup.-2 g/m.sup.2day or more and less than
1.0.times.10.sup.-1 g/m.sup.2day [0117] B: 1.0.times.10.sup.-2
g/m.sup.2day or more and less than 2.0.times.10.sup.-2 g/m.sup.2day
[0118] A: less than 1.0.times.10.sup.-2 g/m.sup.2day
TABLE-US-00002 [0118] TABLE 2 Degree of hardness of Winding-up
organic film Thickness Water vapor tension (pencil of inorganic
permeability Evaluation of Experiment (N/m) hardness) film (nm)
(g/m.sup.2 day) performance 13 10 3B 60 4.8 .times. 10.sup.-1 D 14
30 3B 60 3.2 .times. 10.sup.-2 C 15 150 3B 60 1.8 .times. 10.sup.-2
B 16 500 3B 60 1.4 .times. 10.sup.-2 B
[0119] As understood from Table 2, the functional film, which has
been manufactured so that the degree of hardness of the coating
film is 3B or more and the winding-up tension is kept at 30 N/m or
more, is improved in the performance of water vapor permeability.
Consequently, the occurrence of faults such as cracks and peel-off
of an inorganic film can be reduced by the presently disclosed
subject matter.
Example 3
[0120] Further, a film roll 42 was wound up using a lay-on roller
90 illustrated in FIG. 3 under the conditions of Experiments 1 to 7
shown in Table 1. That is, the film roll 42 was wound up in a state
of being nipped by a lay-on roller 90. In this case, the winding-up
tension was controlled together with the touch pressure of the
lay-on roller 90. Note that the touch pressure of the lay-on roller
90 was applied so that it was 10 N/m to 100 N/m.
[0121] The functional film 10 manufactured using the lay-on roller
90 was subjected to an evaluation for the water vapor permeability
performance according to the same evaluation criteria in Example
1.
TABLE-US-00003 TABLE 3 Degree of hardness of Winding-up organic
film Thickness Water vapor tension Lay-on (pencil of inorganic
permeability Evaluation of Experiment (N/m) roller hardness) film
(nm) (g/m.sup.2 day) performance 17 30 Provided 4B 60 2.1 .times.
10.sup.-3 D 18 150 Provided 4B 60 2.0 .times. 10.sup.-3 D 19 500
Provided 4B 60 1.5 .times. 10.sup.-3 D 20 10 Provided 3B 60 2.5
.times. 10.sup.-3 D 21 30 Provided 3B 60 1.8 .times. 10.sup.-4 B 22
150 Provided 3B 60 9.5 .times. 10.sup.-5 A 23 500 Provided 3B 60
8.7 .times. 10.sup.-5 A
[0122] From the comparison between Experiments 1 to 7 and
Experiments 17 to 23, as for the functional film, which has been
manufactured so that the degree of hardness of the coating film is
3B or more and the winding-up tension is kept at 30 N/m or more,
the performance of water vapor permeability of the manufactured
functional film can be improved by using a lay-on roller during
winding-up a film roll by a coating film forming apparatus.
* * * * *